The overall objective of this project is to conduct a comprehensive investigation to determine the relationship between HIV-1 gene transcription and the disease progression, and to determine the mechanism of differential RNA expression between asymptomatic subjects and AIDS patients. The specific aims of the projects are: 1) To correlate the level of HIV-1 gene transcription with disease progression. The levels of unspliced (e.g. gag) and multiple spliced (e.g. tat) in peripheral blood mononuclear cells (PBMC) will be measured by a newly developed internally controlled PCR assay. The levels of HIV-1 RNA in plasma will measured by a branched DNA signal amplification assay. 2) To evaluate the role of state of the HIV-1 genome (unintegrated and integrated) in differential viral RNA expression. The levels of anchor PCR. 3) TO elucidate the mechanism of maintaining unintegrated viral DNA. Role of nuclear translocation of proviral DNA and the activation state of host cells will be examined. Longitudinal lymphocyte and plasma samples from subjects who developed AIDS and those who remained asymptomatic in the Multicenter AIDS Cohort Study will be used for this study. The project is a direct extension of our preliminary studies in which the levels of HIV-1 RNA in plasma and PBMC are maintained in subjects who remain asymptomatic. The proposed project will provide accurate information whether the increased viral transcription is correlated with the development of AIDS and whether it can be used as early predicting markers for the development of AIDS. Such information will be extremely helpful for patient management and for evaluation of efficacy of antiretroviral drugs. Furthermore, elucidation of the mechanism for differential HIV-1 transcription between subjects who develop AIDS and those who remain asymptomatic will be extremely useful in designing intervention strategy to limit viral expression and thereby controlling pathogenesis.